• Johannes Thumshirn's avatar
    scsi: don't BUG_ON() empty DMA transfers · fd3fc0b4
    Johannes Thumshirn authored
    Don't crash the machine just because of an empty transfer. Use WARN_ON()
    combined with returning an error.
    
    Found by Dmitry Vyukov and syzkaller.
    
    [ Changed to "WARN_ON_ONCE()". Al has a patch that should fix the root
      cause, but a BUG_ON() is not acceptable in any case, and a WARN_ON()
      might still be a cause of excessive log spamming.
    
      NOTE! If this warning ever triggers, we may end up leaking resources,
      since this doesn't bother to try to clean the command up. So this
      WARN_ON_ONCE() triggering does imply real problems. But BUG_ON() is
      much worse.
    
      People really need to stop using BUG_ON() for "this shouldn't ever
      happen". It makes pretty much any bug worse.     - Linus ]
    Signed-off-by: default avatarJohannes Thumshirn <jthumshirn@suse.de>
    Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
    Cc: James Bottomley <jejb@linux.vnet.ibm.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: stable@kernel.org
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    fd3fc0b4
scsi_lib.c 83.4 KB